Attachment for rotary impact tools



Feb. 6, 1951 M. H. BODEN ATTACl-IMENT FOR ROTARY IMPACT TOOLS Filed May 20, 1949 IIIII @A g m m In van for MARSTOA/ BODE/V A Q GAM- 9 6/3 Hzzormey Patented Feb. 6, 1951 UNITED STATES PATENT OFFICE ATTACHMENT FORROTA-RY IMPACT TOOLS Marston H. Boden, Weston, Mass.

Application May 20, 1949, Serial No. 94,406

17 Claims.

1900, or more per minute, they are much em-- ployed, when fitted with attachments as maybe needed, for such operations as tapping, drilling,

reaming, nut running, boring, screw driving stud removing, hole :sawing, wire brushing, buffing,

and the like. Rotary impact tools themselves as H a class are characterized by having as fundamentals of structure: (a) a motor which may be electric, or air driven; (ii) a reciprocable hammer member which is rotatable from the motor; (0) an anvil member which is normally engaged by the hammer so as to be rotatable thereby but from which the hammer is disengageable as the tachment by which a rotary impact tool may be. used as the power source for those operations for which reciprocating impact tools are ,now designed as the. power source. Since both types of impact tools are relatively expensive the use ofthe attachment constituting the present ins/en! tion means the elimination of a material item of tool cost, a factor of importance both in small result ofmovement away from the anvil; (r1) resilient mean'srnorm'al-ly but releasably maintaining the hammer and anvil in operative engagement; and (a) structure cooperating with the hammer an'df-unctioning as a clutch so that :upon a stalling of the anvil, as when a nut is fully run on, to give but-one example here, the hammer is automatically withdrawn from the anvil without any interruption in motor operation. The free end of the anvil is usually squared or otherwise shaped to fit as a driver into a work-engaging tool pieceor to receivela-socket-or chuck for holdingsucha tool piece.

(It :is to be noted that the various operations listed above for which rotary impact tools are employed all involve rotation :of the work-engag i-ng tool piece itself and of its socket, chuck, or the like used. In view of this, it will therefore lee-seen that such impact tools are unsuited for those many operations which are best or are necessarily performed by impacts directed substantiallylineally. For s-uc-hroperations the power source is a reciprocating impact :tool or power oliiectof the present invention to provide an atshops, where economy requires that one power tool be .used for. as many operations as possible, I

and also in large shops where many such power tools may beemployed.

,Itis a further object of the present invent-i011 to provide an-attachment for rotary impact tools.

by which certain operational economies may be eifected as the result of substituting lineally directed impacts for torsionally applied impacts. To. give one specific example here, when a rotary impact tool of /2" drive and capacity is used with a rotary drill for drilling holes mmasonry, concrete, or brick, a hole diameter of .is the, maximum practicable, but at even smaller diam eters the hole to be drilled may become glazed; over ,so that the rotating drill cannot function or so that its progress is slowed up or stopped altogether. In addition, the performance of such; drilling by rotarymeans requires that the operatorv himself supply the lineal pressure to .efiect penetration into the work, and this results in, fatigue. Moreover, the drills themselves, by rear son of the high'resistance which such work ofiers, become quickly dulled and may be easily broken. It will therefore be appreciated that by using .for. such purposes a rock drill, which requires for its operation a succession of blows along its length, the difliculties presented by glazing are eliminated and those presented by dulling and breakage are minimized, and that by using with a rotary impact tool as the power means for such drilling an attachment which translates torsional :Eorce into blows directed substantially lineally, the

fatigue on the operator is minimized since the attachment and the impact tool together act to, causethe work penetration which the operator would'otherwise-have to efiect by pressure exerted lineally by himself.

To the accomplishment of these objects and of others-which will appear hereinafter, the Marious .features of the present invention reside in constructions and vformations all fully described in the followin specification and then set fiorth int-he appended claims the subject matters 1-01 which possess advantages which will be readily anparentyito those skilled in the art andnin the use :of yrotaryrand reciprocating impact tools.

'"The various features of the present invention will be readily understood from reading this v specification connection with the .accom'pany fing drawing which :lillustrates the 'best physical embodiments of the claimed invention at present known to the inventor and in which:

Fig. l is a detail view in sectional elevation of the forward portion of one type of rotary impact tool thousands of which are now in general use;

Fig. 2 is a view in plan of one embodiment of the present invention as used with a star drill;

Fig. 3 is a view in elevation of the embodiment shown in Fig. 2, the body passage receiving the square driver of a rotary impact tool;

Fig. 4 is a view in end elevation of the Figs. 2-3 embodiment;

Fig. 5 is a view in elevation of an alternative embodiment of the present invention, in association with a socket used with the driver of a rotary impact tool;

Fig. 6 is a view in end elevation of the Fig. 5

embodiment;

Fig. 7 is a detail view in elevation, partially in section, showing an alternative socket used in an embodiment which maybe otherwise like the Figs. 2-4 embodiment;

Fig. 8 is a detail view in elevation, partially in section, showing an alternative socket used in an embodiment which may be otherwise like the Figs. 5-6 embodiment;

Fig. 9 is a view in elevation of a modification of the Figs. 2-4 embodiment, characterized by the absence of the grip extension shown in Figs. 2 and 3.

Fig. 10 is a view in elevation, partially broken away, of an embodiment of the present invention provided with an angularly disposed extension; and

Fig. 11 is a view in elevation of an embodiment of the present invention corresponding to Fig. 10 but having a tool socket located in the angularly disposed extension.

Referring to the drawing, the rotary impact tool detailed in Fig. 1 is of the type adapted to be held in one hand by means of a pistol grip, is trigger-operated, and is provided with an electric motor and means for reversing the motor as circumstances of the work reouire. These elements are not shown because they are old and well known and form no part of the present invention. In the forward portion of the tool housing, indicated by the numeral I5, is a rotatably mounted frame I6 operatively connected to gearing (not shown), and mounted reciprocably on the frame l6 for rotation therewith is a hammer member I! the forward end portions of which are shaped to engage corresponding portions on the rear of an anvil member 18 rotatably mounted in the forward portion of the housing IS. A spring I9 coiled about the frame [9 functions to maintain the hammer I? and anvil it! normally in engagement so that the former drives the latter, but the reciprocability of the hammer on the frame I 6 and the surface formation of those portions of the hammer and anvil which engage each other are such that partial or absolute resistance to rotation exhibited by the anvil I8 results in the hammer ll automatically moving rearwardly on the frame I6 (to the right, viewing Fig. 1) and ridin off the anvil, this action being made possible by a clutch construction comprising cam balls and cooperating grooves therefor forming part of the frame and'hammer structure. With this arrangement, the motor and frame [6 rotate continuously even when the anvil I8 is stalled, and since the spring 19 tends to maintain the hammer and anvil normally in engagement, .the hammer is repeatedly urged into engagement with even a stalled anvil.

As a result, the hammer delivers a succession of torsional impacts on the anvil at the rate of 1700-1900 or more per minute, even though rotation of the anvil under the force of such impacts is impossible. This rapid succession of impacts by the rotating hammer on a stalled anvil is the basis for the operation and functioning of the attachment constituting the present invention.

Further structure shown in Fig. 1 comprises the integral forward end member 2| of the anvil I8, which extends outwardly of the housing I5, is shown as square in cross section for illustrative purposes only, may be provided with a conventional spring-pressed plunger 22 for retaining a socket or tool piece, as is well understood, and is referred to as the driver 2| in the remainder of this specification. The details of rotary impact tool structure are illustrated in many patents and other printed publications, but for a few specific citations of such patents under which such tools are now made and marketed, reference is here made to the Pott patents, No. 2012,916, granted August 27, 1935. and No. 2,049,- 2'73, granted July 28, 1936, to the Thomas patent, No. 2,463 656, granted March 8. 1949, and to the patents cited on the last page of said Thomas patent.

The attachment constituting the Figs. 2-4 embodiment of the present invention is provided with a rod-like body 23 which is preferably of integral construction and is shown as being a straight length which is circular in cross section, although it may have any suitable cross section desired. Ad acent one end of the body 23 is provided with a tapered passage 24 which may extend through the body transversely thereof, i. e., at substantially to the longitudinal axis of the body, and functions as a holder or socket for receiving the tapered end 25 of the shank ofa work-enga ing tool piece herein illustratedmerely for disclosure purposes as a star drill 26. Spaced from the socket 24 the body 23 is provid d with a second passage 27 which also may extend through the body transversely thereof, i. e.. at substant ally 90 to its axis, but the axis of the passage 21 is itself at substantially 90 to the axis of the socket 2G. The passage portion 21 is shown as shaped square in cross section merely for illustrative purposes, and is so shaped to function as a socket for receiving nonrotatablv the square driver 2| of the rotary impact tool, as indicated in Fig. 3. With this construction the driver 2! and the passage portion 2! are coaxial when the former is inserted in the latter, and th s coaxiality is at substantially 90 to the axis of the socket 24. Alternatively stated, the axis of the holder or socket 24 lies in a plane which the axis of the passage 2'! intersects at substantially 90.

Further structure of the Figs. 2-4 embodiment comprises the remainder of the body 23 which functions as an integral extension or grip 28 which is coaxial, if desired and as shown, with the body 23 and which an operator may grasp to support and steady the body and the star drill 25 held by the socket 24. The socket or holder 24 is thus located at one side of the driver passage portion 2'! and the extension 28 is located at another side of the passage portion 21.

In using the Figs. 2-4 embodiment of the present invention, an operator may grasp the extension 28 in his right hand. for example, so as cated in Fig. 2 with the bit of the star drill 26 engaged with TH, stationary (masonry or :rocksurf-aceis. The rotaryimpact t'ooLaset ;to rotate the "frame l6 and the hammer I! in a clockwise dimention, .is held :in the operators left hand with the driver 2! directed downwardly and inserted in thedriverpassage 27. With the impact tool so held, the axis of rotation of the driver '2! is at 90 'to the longitudinal axis of the body 23, and with this arrangement it will be apparent that if the trigger of the impact tool be depressed, -thetend'enc-yof the hammer l to rotate the anvil IBclockwisewill cause the driver 2] to tend to rotate thebod-y 2'3,the star drill 26, and the extension 28 as a unit clockwise about theax'is of the driver. But actual rotation in this manner does'n'ot'take place because it cannot-for theengagemerit o'f the star drill with the stationary surface 8 makes such rotation impossible. The

body 23, star drill Z6, and extension '28 thus remain stationary, i. e., non-rotative, as it were,

andas a 'consequence'the hammer ll ridesup- "Wardly off the anvil, but the action of the spring 'The torsional impacts 'appliedto the anvil as by the'rotating hammer i i are transferred clockwise to the driver 21 because the driver is an integral'part of the anvil, and'as a consequence the driver -applies torsional impacts clockwise to the body "23 because the driver is inserted in the'body portion "passage 21 which is shaped to receive the driver "in non-rotative engagement. Since the-body 23 cannot rotate, the "force of these impactsis transferred -by the body to to the socketed end25 of the'star drill 26 and thence longitudinally of the star drill to its b'it engaged with the work, and sin'cethe direction of rotation of the hammer 11 is clockwise, the transferred torsional impacts drive the star drill ubstantially axial y toward, i. e.,.into, the work sothat the surface S is "subjected bythe star drill to successive blows delivered with great rapidity and force in a sul stantially lineal manner. During the delivery of these impacts the star drill may be turnedabout its own axis, as is'necessary in the use 'of'such l drills, by the operator simply'swinging the extension 28 and body 23 small amount about the star drill axis as a cententheimpact tool itself being tilted during such swinging to maintain the axis of the driver 26 at substantially 90 to that of the body 23.

Analternat'e, and for some purp cses mor ea ily performed, manner of operating the Figs. .24 embodiment is to hold the body 23 andextenti'on"28vertically"inparallelism with the surface 'S',ithe1holder'24 and star drill ZG'bein aboVe and the extension .28 being below. The right hand "of the operator may again be used for this purpose and for holding the star drill against the surface .S, but the impact tool, this time .set to cause "rotation of th'effr'ame l6 "and the hammer H in 1a counter-clockwise direction, wouldlbe-held horizontally by the left hand and the driver 2! would :be inserted into the left end of the passage portion 2?. Depression of thetrisger of the impact tool would cause torsionalimcacts to be delivered by the hammer IT in ajcounter-clockw i'se manner to the anvil l8, and these would betransferred'by the driver 25 to thebodyES and by Lt-h'ebndy? to the star drill 15; substantially. enemy-"theatres effect repeatedfblows of the- 6, star rdrill ton-"the surface :S in @a manner corresponding to that set forth in the immediately preceding paragraph. Should the body 23 and extension 28 be held verticall by the left :hand and the "impact tool beheld horizontally by the right, the latter would, :of course, be set to operate :in a clockwise manner because the impact tool would itself be located to the right of the body 23 and extension 2.3. 'But whicheverhand would be used to "grasp tlce extension, is will be seen that the extension may easily be swung small amounts, and the impact tool correspondingly tilted from the horizontal, to turn the star 'dril-I 26' about it own axis during repeated impacts thereon while in engagement with the work.

Si-n'ce either of the above modes of operation tends to cause the star drill shank "end 25 to be forced tigh'tlyinto thesocket-Zt, it maybe noted at tliis point that'by disengaging the star "drill 26 from the surface-S while maintaining a grip on the extension 28 or the body 23 and by then re- Vers'ing the direction of rotation of the motor to reverse the direction of impact transference to the body -2 3 by the driver 2 I, the resultin vibration tends to loosen the shank end 25 in the socket 24 so that the star drill 'falls out or may be easily removed.

It is realized that since the impacts delivered by the driver 2! to the body 23 are torsional'imacts, their force is not directed by "the -bodv along the *exac't l'ongitudinal'axi of the star drill 26, as is the-case byablow properly delivered on the end of a star drill in the usual'mannerby a sledge. But the body 23 necessarily causes "the impacts to be delieverd in close approximationto the exact 'axiality of the star drill, and as their force is directed longitudinally of the shank or the star drill, the torsional impacts of the driver 2! are translated by the body'into impacts which are substantially lineal. A factor "here in the practical translation of torsion to lin-eality is'the fact that the body portion passage 72! "is spaced from the socket 23,1. e., the "latteris located at one side of the former. If the passage portion 21 were located directly over the socket 2'4, for example, it will beseen from Fig. 2 that "the star drill as a whole would become a radius the center for swinging o'fwhich would be its 'socket'ed end .25, and "as a consequence there would .be a s roll? tendency for the opposite or bt end of the star drill to swing varcuate'l-y away from the surface S .as the immediate result of each impact of t e hammer '5'? upon .theanvil L8. This would be the case because the driver I2l engages the passage portion .2 on at least two-opposed-areas, and the impact force 'which is delivered to the body 23 .by onedriver face orlportion thereof and which would tend to cause the star drill to bite into the surface S would be equalled, or substan-- tially equalled, by the impact force which is delivered to the body 23 by another driver face or portion thereof and which would tend to cause the star drill as a whole to swing arcuately'away from the surface S about the axis of the driver 2!. Under such conditions the operator would have t-o use maximum effort, for "in addition "to grasping the extension 28 "to support the body 23 and star drill "while maintaining'the latter engaged with the surface S "in counter-actiomto the natural tendency of the star drill to'boun'ce directly back from 'the Work under the influence of the impacts delivered on its socketed end, "the operator would also have to grasp the extension.

28 so as to counteract the tendency of the star drill as a whole to swing arcuately away from the surface S.

By increasing the length of the radius about which the star drill 26 tends to swing arcuately, the force of this tendency to swing away from the surface S may be reduced and minimized and simultaneously the force of the tendency of the star drill to bite into the surface S may be increased, and this is accomplished by spacing the passage portion 21 from the holder or socket 24, i. e., by locating the holder 24 at one side of the passage portion 21. Taking Fig. 2 as merely one illustrative example of such spacing, it will be seen that the distance between the axis of the passage portion 21 and the center of the front face of the bit of the star drill 26 is greater than the length of the star drill itself. If an imaginary line be considered as drawn between these two points, it will be seen that the angle between such a line and the longitudinal axis of the body 23 is materially less than 90, and from this it follows that if such imaginary line were swung about the axis of the passage portion 21 to a position of being at 90 to the surface S, the forward end of the imaginary line would be located behind and beyond the surface S and not at it, as is the case of the front face of the bit of the star drill 26 in Fig. 2. As a consequence, a portion of the force which would tend to cause the star drill to swing arcuately away from the surface S were the passage portion 21 located directly over the holder or socket 24 is, in the Fig. 2 spacing illustration, utilized as an additional force increment tending to urge the star drill to bite into the surface S. The existence of spacing between the socket or holder 24 and the passage portion 21 thus reduces and minimizes the tendency of the star drill to swing arcuately away from the work and as a consequence reduces and minimizes the effort required of the operator to counteract such tendency.

From these considerations it follows that the greater the distance between the holder or socket 24 and the passage portion 21, i. e., the greater the distance between the center of the front face of the star drill or other tool piece mounted in the holder 24 and the axis of the passage portion 21, the less will be the tendency of the tool piece to swing away arcuately from the work and the greater will be its tendency to bite into. the work. As theoretical matter this spacing may thus be very large indeed, but considerations of weight, size, and ease of handling of embodiments of the present invention place practical limitations on the above distance or spacing possibilities. Where an impact tool has a driver of less than A square size, one practical distance between the holder or socket 24 and passage portion 21 axes can be as little as 2" or may be larger. Where an impact tool driver is of /2" square size, a distance of 3" between these axes is more satisfactory, and where the size of the driver is greater than' a spacing of more than 3 between these axes is desirably employed. It should be understood, however, that these spacing distances are not critical for any given embodiment, but it is desirable that the spacing not be so great that when in use a body 23 will exhibit appreciable flexing between these axes under the force of the impacts from the driver 2|. The axes spacing shown in the various Fig-'- ures is thus to be considered as exemplary only.

The structure shown in Figs. 2-4 is designed to receive the driver member 2! directly, but since manufacturers of these impact tools supply re movable sockets for the drivers in the interest of greater adaptability of the tools, an alternative embodiment of the present invention, in all other respects identical with the structure shown in Figs. 2-4, may be provided with a body 29 (Figs. 5-6) having an integral boss or fixed projection portion 30 as a substitute for and in the location of the Figs. 2-4 passage portion 21. The portion 30 is shown as shaped hexagonally in cross section merely for illustrative purposes, and is so shaped to receive non-rotatively the hex end of an adapter in the form of a socket member 31 of conventional construction, the other end of which is squared to receive the driver 2!, as illustrated in Fig. 5. Since the projection portion 38 serves the same function for the socket member 3| as the body portion passage 21 serves for the driver member 2|, the axis of the projection 3i) transversely of the body 29 is at substantially to the axis of the holder or socket 24, as indicated best in Fig. 6, i. e., the axis of the transverse extension 32 intersects at substantially 90 a plane in which the axis of the holder 24 lies. Impacts delivered torsionally to the driver 2! are transferred to the socket member 3| and so to the projection portion 38, by which they are in turn transferred to the body 29 and substantially lineally to the star drill or other tool piece mounted in the holder 24 in a manner which will be readily understood from the above considerations about the Figs. 2-4 embodiment.

The sockets or holders 24 in the Figs. 2-6 embodiments are shown as tapered and as extending through the bodies 23 and 29 merely for illustrative purposes, but it is not necessary that they extend all the way through in either case or that they be tapered. Tool pieces for performing operations such as those listed in the last sentence of the third paragraph of this specification are provided with straight or cylindrical shanks as well as with tapered ones, and for. such tool pieces bodies 23A (Fig. 7) and 29A (Fig. 8) may be employed which in all other respects are identical with the embodiments of the present invention shown in Figs. 2-6. Instead of a tapered socket 24, however, each of these bodies 23A and 29A is provided with a blind end passage 32 which has the same location as a holder or socket 24, has an axis at substantially 90 to that of the passage portion 21 or projection portion 38 as well as to the longitudinal axis of its body 23A or 29A, respectively, as is the case of the socket 24, and functions as a holder for the end of the cylindrical shank 33 of a suitable work-engaging tool piece. Should the shanks of given tool pieces be other than circular in cross section, the blind end passages 32 may, of course, be correspondingly shaped. The Figs. 7-8 embodiments of the present invention thus function for tool pieces having straight shanks in the same manner as the Figs. 2-6 embodiments function for tool pieces having tapered shanks, and the Figs. 7-8 embodiments are handled and employed as above stated for Figs. 2-6.

In Fig. 9 there is shown an embodiment of the present invention characterized by having a body 233 from which the extension 28 shown in Figs. 2, 3, and 5 is omitted. Since the Fig. 9 embodiment is provided with the above-described holder or socket 24 and passage portion 21, it will be ap-' parent that impacts delivered torsionally to the driver 2| by the impact tool are translated intov substantially lineal impacts upon the end of a star drill, for example, used with the body 233, all in the manner described above, but that since the extension 28 is omitted. the body 233 and tool piece held thereby must be supported differently than described above. This is accomplished by the operator supporting the impact tool in whichever hand may be convenient and then grasping with his other hand the portion of the body 233 which lies forwardly of the tool piece socketed in the holder 24. The grasping hand will be located at the base of the tool piece so that its tendency to bounce back from the Work axially underthe influence of the impacts delivered by the driver 2| may be easily counteracted by the operator. It will be understood, of course, that if desired there may beprovided a body whichis otherwise identical with the body 233 shown in Fig. '9 but having the Figs. 5-6 projection portion at substituted for the passage portion 2'! and/or having the blind end passages 32 of Figs. L8 substituted for the holder or socket 2 3.

In using the above-described embodiments of the present invention and the modifications sug- :gested, it will be apparent that if the trigger of the impact tool is never depressed until the body extension or body is steadied by the operator there will be no danger of the embodiments and tool pieces held thereby being spunlaround inthe :air, i. e., out of engagement with a surface or where they might endanger the operator by striking him. To provide a safety feature, however, which will prevent such spinning in the event of premature or accidental trigger depression, an embodiment of the present invention such as shown in Fig. 10 may be provided, having a body 23C which in all other respects may be identical with the body 23 in Figs. 2-4 but which has a two-part integral extension, one part 34 of which is coaxial with the body in the manner of the extension 28 in Figs. 2, 3, and :5 and the other part. of which extends from the part ed as an integral arm shown as'bent upwardly at substantially 90 to the part 34. The length of the extension part 34 is such that the distance between the axis of the holder or socket 224 and the:extension arm 35 is slightly greater than one half the Width of the housing I! of the impact tool, so that with the impact tool driver 2! .inserted in the passage portion 2'l,'the housing It will :clear the arm '35 and be parallel therewith. The length-of the arm 35 is preferably such as to at least reach the forward portion of the pistol grip of the impact tool, and may be longer. With this construction, rotation of the body 230 and extension parts 34 and 35 as a unit upon accidental'depression of the tool trigger results in movement through an arc of less than 360 before the arm part 35 strikes the pistol gripand is stopped, and there is no danger of the Fig. 10 embodimentand tool piece mounted thereon striking the operator and causing injury. In using the Fig. l0 embodiment, the operator'would normally have the body 230 located vertically and would steady and support the embodiment by pushing on the portion of the body lying forwardly of the holder 24, in the same manner as described above for the embodiment shown in Fig. 9,and in this connection it is to be noted that since the operator would support the impact tool horizontally with the driver 2! inserted in the passage portion 21, the driver itself would furnish part of the support for the weight of the extension portions 34 and .35.

Instead of having an embodiment characterized by a safety arm extension located on the right, as shown in Fig. 10, there may be provided an embodiment in whichthe-safety arm extension is son the left and in which "the toolpiece 'holderiit- 10 self is located. Such an embodiment is shownzin .Fig. .11, and is provided with a body 36 corresponding to the body 2300f Fig. .10. in that it has at one end the transverse passage portion 2.1for receiving the driverZzl :as above described, ibutrisqing at substantially'iifl" from the other end is an extension arm corresponding to the extension part 3-5 in Fig. 10in length and function, and at the upper end of the extension 3? :a tool piece holder is located, shown illustratively as the socket 24. The length of the body 36 is such that the distance between the passage portion 21 and the extension .31 is slightly greater than one half the-width of the impact tool housing 115, and

with this. construction it will .be seen that should the trigger bedepressed accidentally when-the tool piece is not engaged with the Work, the exetension 31 will strike the pistol :grip inless than 360 of turning andwill be stopped. The axis of the holder or socket .24 is at substantially -'to the longitudinal .axis of the extension 3,? .and of the body .36 andis also at substantially 90 to-the axis .of "the passage portion .21. Torsional impacts delivered by the driver 21 are thus transferred to the body :26 and by it to the extension 35!, .sothat the force of these impacts is directed substantially lineally longitudinally of the tool piece mounted in .the holder or socket 24. In using the Fig. 11 embodiment, the operator would push .rearwardly .on, .i. .e., would grasp, the .portion .of the extension .3] which .lies forwardly of the holder or socket 24, and .if the extension .31 be post-- .tioned vertically in use it would :be supported by the operator's grasping handfor the-impact tool would .be vertical, .butif the extension .3? is posttioned horizontally, it. would be supported impart by the driver :Zi :because the impact tool would also be held horizontally.

It will :be appreciated that vthe holder or .sochet 24 and the passage portion 21 have beenshown, in. Figs. lO-and ll merely for illustrative purposes, and that these embodiments may alternatiael lbe provided with .thetproiection portion 30 of Figs. 5, and 8 and/or .With the blind end passage32 .of Figs. '1 and 8. It will also beappreciatedthat while the Fig. 10 embodiment may be considered as being right handed, a corresponding structure may be madeleftihandedand that theaopposite is true of the Fig. :lltembodiment,

Embodiments of th pre nt inven io m be made of any material suitable for their purpose. It is preferred-however, thatthev be mad of forged .steel, suitably heat treated for strength and to withstand shock.

What is claimed as'newris; i

F r. use with a device adap e t r ns ate continuous rotary movement into intermittent torsional impacts and provided with .a member which is rotatable about .an axis to deliver such impactsand which forms part of the device: an attachment comprising ;a rod-like body having a portion shaped to receive said device member non-.rotatively so that the impacts of the meme ber may be delivered to the body, said body also :having :a holder which is anin esr pa of the body and is zlocated atone side :said shaped portion for receiving atool piece adapted .to act on the work under the'liniluence of said impacts.

F r-use with a d v a pt d o trans a e continuous :rotary movement into (intermittent torsional impacts and provided with ;a member whichis rotatable about an axis to deliverguch impacts and which iorms part of the dc ice; an attachment omprising a r -like ho vh vine 13;.SDOYti-QI1 shaped- :to receive aid device member non-rotatively so that the impacts of the mem ber may be delivered to the body; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the work under the influence of said impacts, said holder being so located with respect to said shaped portion that the axis of said tool piece is angularly disposed to the axis of said device member when the member is received by said shaped portion.

3. Structure such as set forth in claim 2 characterized by the fact that the shaped portion is a socket extending transversely of the body.

4. Structure such as set forth in claim 2 characterized by the fact that the shaped portion is a fixed projection extending from said body transversely of its axis.

5. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like body having a portion shaped to receive said device member non-rotatively so that. the impacts of the member may be delivered to the body; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the Work under the influence of said impacts, said holder being so located with respect to said shaped portion that the axis of said tool piece is angularly disposed to the axis of said device member when the member is received by said shaped portion; said body also having a portion located generally at another side of said shaped rmrtion and functioning as an extension of said body for gripping by the user.

6. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like body having a portion shaped to receive said device member non-rotatively, said shaped portion having an axis which is angularly disposed to the longitudinal axis of the body so that the impacts of said device member when it is received by said shaped portion are delivered to the body at an angle to its longitudinal axis; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the work under the influence of said impacts, said holder having an axis which is angularly disposed to the longitudinal axis of the body and to the axis of said shaped portion.

'7. Structure such as set forth in claim 6 characterized by the fact that the shaped portion in a socket extending transversely of the body.

8. Structure such as set forth in claim 6 characterized by the fact that the shaped portion is a fixed projection extending from said body transversely of its longitudinal axis.

9. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like body having a portion shaped to receive said device member non-rotatively, said shaped portion having an axis which is angularly disposed to the longitudinal axis of the body so that the impacts of said device member when it is received by said shaped portion are delivered to the body at an angle to its longitudinal axis; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the work under the influence of said impacts, said holder having an axis which is angularly disposed to the longitudinal axis of the body and to the axis of said shaped portion; said body also having a portion located generally at another side of said shaped portion and functioning as an extension of said body for gripping by the user.

10. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like body having a portion shaped to receive said device member non-rotatively, said shaped portion having an axis which is at substantially to the longitudinal axis of the bod so that the impact of said device member when it is received by said shaped portion are delivered to the body angularly to its longitudinal axis; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the work under the influence of said impacts, said holder having an axis which is angularly disposed to the longitudinal axis of said body and which lies in a plane which the axis of said shaped portion intersects at substantially 90.

11. Structure such as set forth in claim 10 characterized by the fact that the shaped portion is a socket extending transversely of the body.

12. Structure such as set forth in claim 10 characterized by the fact that the shaped portion is a fixed projection extending from said body transversely of its longitudinal axis.

13. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like body having a portion shaped to receive said device member non-rotatively, said shaped portion having an axis which is at substantially 90to the longitudinal axis of the body so that the impacts of said device member when it is received by said shaped portion are delivered to the body angularly to its longitudinal axis; said body also having a holder which is an integral part of the body and is located at one side of said shaped portion for receiving a tool piece adapted to act along its longitudinal axis on the work under the influence of said impacts, said holder having an axiswhich is angularly disposed to th longitudinal axis of said bod and which lies in a plane which the axis of said shaped portion intersects at sub stantially 90; said body also having another portion located generally at another side of said shaped portion and functioning as an extension of said body for gripping by the user.

14. Structure such as set forth in claim 13 characterized by the fact that the shaped portion is a socket extending transversely of the body.

15. Structure such as set forth in claim 13 [3 characterized by the fact that the shaped portion is a fixed projection extending from said body transversely of its longitudinal axis.

16. For use with a device adapted to translate continuous rotary movement into intermittent torsional impacts and provided with a member which is rotatable about an axis to deliver such impacts and which forms part of the device: an attachment comprising a rod-like bod having a portion shaped to receive said device member non-rotatively so that theimpacts of said member may be delivered to the body; said body also having a holder located at one side of said shaped portion for receiving a tool .piece adapted to act on the work under the influence of said impacts; said body also having an extension located generally at another side of said shaped portion and angularly disposed to the axis of said body.

17. For use with a device adapted to translate continuous rotary movement into intermitten torsional impacts and provided with a member which i rotatable about an axis to deliver such impacts and which forms part of the device: an

14 attachment comprising a rod-like body having a portion shaped to receive said device member nonrotatably so that the impacts of said member may be delivered to the body; said body also having an extension located generally at one side of said shaped portion and angularly disposed to the axis of the body, said extension being provided with a holder for receiving a tool piece adapted to act on the work under the influence of said impacts.

MARSTON H. BODEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 673,697 Breckenridge May 7, 1901 734,825 Croft et al July 28, 1903 1,598,090 Lacrocca Aug. 31, 1926 1,660,579 Roth Feb. 28, 1928 1,789,712 Ridgway Jan. 20, 1931 Certificate of Correction MARSTON H. BODEN i It is hereby certified that error appears in the printed specification of the aboye numbered patent requiring correction as follows:

Column 4, line 35, after end strike out of; column '6, line 70, after counter and before action strike out the hyphen; column 11, line 62, for the words portion in read portion is and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of thefilcasej in the Patent Oflice. Signed and. sealed this 3rd day of April, A. D. 1951. 

